Magnetic means and method of tensioning



April 13, 1937. E. G. PARV IN 2,077,183

MAGNETIC MEANS AND M ETQOD OF TENSIONING Filed Feb.6, 1936 2Sheets-Sheet 1 :i H i a '7 7 l n -9 I M Q II F R f 5 /4 as za 26: a l /8Z /\9 E E INVENTOR.

E Edward G Parvm ATTORNEYS.

April 13, 1937. E. G. PARVIN v I 2,077,183

MAGNETIC MEANS AND METHOD OF' TENSIONING Filed Feb. 6, 1936 2Sheets-Sheet 2 INVENTOR. Edward G. Pan/[n BY 2 Q Q AZEFORNEA'S.

Patented Apr. 13, 1937 UNITED STATES MAGNETIC MEANS AND METHOD OFTENSIONING Edward G. Parvin, Roselle, N. J.', assignor, by

mesne assignments, to Syncrofl Machine Company, Newark, N. J., acorporation of New Jersey Application February 6, 1936, Serial No.62,591

method by means of which a substantially constant and uniform tensionmay be maintained upon a web or strand being fed from the flyer of V awinding or wrapping machine.

The prime object of this invention is to provide means particularly inthe form of an electromagnetic drag device for maintaining asubstantially uniform tension upon a web or strand being fed from afiyer cop.

A further object of this invention is to provide a method and means ofthis type for compensating for the loss and weight of the cop as thematerial is fed therefrom and its reduction in diameter. 7

These and many objects as will appear from the following disclosure aresecured by means of this invention.

This invention resides substantially in the combination, construction,arrangement, relative location of parts, steps and series of steps, allas will be detailed below.

In the accompanying drawings,

Figure 1 is a vertical, central, cross-sectional view with some partsbroken away of a portion of a winding machine flyer embodying thefeatures of this invention;

Figures 2 and 3 are plan and side elevational views of the stator corefor the magnetic drag device;

7 Figures 4 and 5 are plan and side elevational views of the pole piecefor the stator core;

Figure 6 is a plan view of the rotor pole piece;

Figure 7 is a vertical, central, cross-sectional view therethrough; and

Figure 8 is a diagrammatic layout of the circuit arrangement of thedevice.

The invention is directed to that type of winding machine employing aserving head through which a strand, cord or wire passes longitudinallyof its length and has wrapped thereon by the serving head a web orstrand of covering material which is applied thereto in the form of ahelical wrap comprising successive turns which may or may not overlap.Such a serving head rotates at high speed, usually on a vertical axis,upon which axis and on the fiyer is journaled a cop'spindle forsupporting a cop or spool of the material to be applied in a helicalwrap. Those skilled in the art fully appreciate that in the operation ofsuch devices and particularly where the web or strand to be wrapped isof a delicate nature that the web or strand is subjectedto a varyingtension because of the loss in weight '5 and reduction in diameter ofthe cop or spool as the material is fed therefrom. This variation intension on the web or strand results in an uneven application of thematerial to the core and may often vary through such a wide range 0 asto result in breaking of the web or strand.

The basic object of this device is to provide a simple and automaticallyacting compensating device by means of which a uniform tension ismaintained on theweb or strand by reason of compensation which isautomatically provided to counteract the reduction in the diameter ofthe cop or spool. The full nature of the invention will be more readilyappreciated after the structure has been described in detail.

a At l is shown a portion of a support, to. which is to be attached theserving head motor, not shown in the drawings. This motor is, attachedto the support so as to depend therefrom and permit of attachment of theshaft of the motor to the spindle 2. Locked on this spindle by a pair ofthreaded lock nuts or rings 3 is a collar 4. This collar is connected bymeans of the ma-,

chine screws 1 to a plate or turntable ,5 so that. it will revolve withthe spindle 2. The collar 4 is seated in a central recess in the centraldepending boss or hub 6 of the plate 5. I

The spindle 2 is provided with an extension 8 of reduced diameter thatpasses up through the plate 5 and through a central recess l4 in the topthereof. v Rotatably mounted on suitable bearing members as illustratedat It is the cop sleeve 9 which is locked in place on portion 8 of thespindle by means of a threaded ring ll. The cop s1eeve 9 is providedwith a flange at the lower end thereof. The u per end of the por tion 8of the spindleis provided with a suitable form of clutch and locking nutl2 by means, of which the nose piece, not shown but usually employedwith these serving heads, is mounted in place.

Attached to the plate 5 in the recess I4 is a stator core 1510fmagnetizable materiahsuch as steel or iron, built in the form of a cuphaving a central integral sleeve l6. Resting on the upper end of thesleeve i6 is the end thrust ball bearing 1 l3 upon which the loaded copsleeve 9 rests so as to be freely rotatable upon the portion 8 of thespindle. As shown in Figure 2, the stator core is provided with a seriesof slots [5' for the purpose of reducing the eddy current losses in thecore in accordance with common practice in the electrical arts. At 2! isa disc shaped cover for the stator l5 built somewhat in the form of aring of magnetic material andnotched to provide the pole pieces Zia.This cover is fixedly securedito the. cup [5 and serves'to enclose thestator winding l1. One terminal l8 of the winding His connected to acollector ring l9. mounted'upon' aninsulating ring 20 secured to the hub6. A, brush, not shown, is pr'ovidedfor completing the circuit to'the'ring H3. The other terminal of the winding ll, although not shown inFigure 1, is grounded on the frame of the machine. Secured to theflanged end of the cop sleeve 9 is the magnetic rotor 22 which isconstructed in the form shown in Figures 6 and 7 and is notched at theperiphery to provide the poles 22a. This rotor is secured to the flangedend of the cop spindle by means of the machine screws 23 for rotationtherewith. The rotor is constructed so as to coincide axially with thestator poles 2Ia, as is clear from Figure 1.

At 24 is shown one of the several guide spindles commonly employed on aserving head around which the web passes in travelling from the cop orspool mounted on the cop sleeve to the nose piece. There is shown,although it forms no part of this invention but is disclosed in one formin the patent to Fantone and Jameson No. 2,044,160, issued June 16,1936, a centrifugal switch which is connected to the control circuit ofthe serving head motor so as to stop if the web breaks. An insulatedcontact 25 is mounted on the guide post 24 and is connected byaninsulated conductor 26 to a collector ring 2'! mounted on theinsulating ring 28. The other wire of the control circuit is grounded onthe machine and the web in passing to the nose piece engages thepivotally mounted lever 29 so as to hold it out of engagement with theinsulated contact 25 until the web breaks.

The circuit for the automatic tensioning device is shown in Figure 8.One terminal of the winding H is diagrammatically indicated as groundedon the machine by means of the lead 33. Its other terminal is connectedby the wire l8 to the collector ring IS. The brush, not shown, whichengages the ring 19 is connected by the wire 3! to the adjustablecontact of a resistor 32. This resistor is connected by the wire 33 to avariable transformer 3 energized from a suitable source. The bestpractice prefers a relatively low voltage on the automatic tensioningdevice so that the connection 33 is taken from the secondary of theenergizing transformer 34 at a point to provide about a 24 voltpotential for the winding H.

In the operation of the device a cop or spool is mounted upon the copspindle 9 so as to be rotatable with it. The end of the web or strandWound on the cop is led around the guide post 24 and to the nose piecein a manner so as to engage lever 29 and hold it out of engagement withthe contact 25. When the cop or spool is full it has a maximum diameterand a maximum weight so that the web fed therefrom in overcoming theinertia of it is under a tension which by proper proportioning of thevarious parts may be the desired tension. However, as the cop losesweight and diameter the tension on the web or strand will increase if nocompensating device is employed.

It is likewise apparent that for a constant linear feed of the web orstrand the cop sleeve will revolve at an increasing rate as the diameterof the cop is reduced. It is here noted, although well known in the art,that the fiyer motor causes rotation of the spindle 2 with its attachedportion 8 and plate 5 with all the parts mounted thereon. In addition tothis rotation, however, the cop sleeve rotates on its bearings l0 aboutthe axis of the spindle. Advantage is taken of this fact in theinvention. Since the cop sleeve has relative motion with respect to thespindle and plate the rotor 22 will have relative motion with respect tothe magnetized stator I5. This stator is magnetized, it will be apparentfrom Figure 8, by the supply of energy from the secondary of transformer34, through wire 33, resistor 32, wire 3|, ring l9, wire l8, and toground at 33 through the winding l1. Thus the stator poles 2la will beenergized and magnetizing currents will be induced in the rotor 22 whichwill magnetize it in a direction to oppose its relative rotation withrespect to the stator poles. The magnitude of this reaction will, over auseful range, vary substantially uniformly with the variation in thespeed of rotation of the rotor 22 with respect to the stator. When thestator is energized with alternating current the drag on the rotor 22will decrease as the relative speed of rotation between the rotor andstator increases over a sufficiently Wide range to make it possible totake advantage of this fact by means varying the amount of resistance ofresistor 32- included in the circuit of the stator winding I1.

It is to be noted, as will be apparent to those skilled in the art, thatthe invention herein disclosed is not limited to any particular type ofwinding or wrapping around. The invention may readily be applied for thepurpose of maintaining a uniform tension in a strand, wire, cord or webof material being fed from a spool, cop, reel or coil of materialregardless of the manner in which the material being fed is employed. Inother words, the device may be employed in any mechanism wherein auniform tension is maintained in a feeding web or strand to compensatefor the reduction in diameter of the spool, cop, reel or coil from whichit is being removed.

From the above description it will be apparent that this inventionresides in certain principles of construction and methods of employingit which may be embodied in other physical forms and carried out inother ways without departure from the true scope of the invention. I donot, therefore, desire to be strictly limited to the disclosurepresented for the purpose of illustrating the invention, but rather tothe appended'claim.

What I desire to secure by United States Letters Patent is:

In a mechanism of the type described the combination comprising aspindle, a coil supporting sleeve journaled on said spindle, amagnetizable' member connected to said sleeve and having a plurality ofpoles, a magnetizable stator having a plurality of poles mounted on afixed support with respect to said sleeve and adjacent said magnetizablemember, and means for creating an alternating current magnetic field insaid stator whereby increase in the speed of rotation of said sleeve asa coil mounted thereon is reduced in stantially uniform tension in thematerial fed from the coil.

EDWARD G. PARVIN.

